diff options
Diffstat (limited to 'pkg/tcpip/header/icmpv6.go')
| -rw-r--r-- | pkg/tcpip/header/icmpv6.go | 35 |
1 files changed, 32 insertions, 3 deletions
diff --git a/pkg/tcpip/header/icmpv6.go b/pkg/tcpip/header/icmpv6.go index 20b01d8f4..4eb5abd79 100644 --- a/pkg/tcpip/header/icmpv6.go +++ b/pkg/tcpip/header/icmpv6.go @@ -54,9 +54,17 @@ const ( // address. ICMPv6NeighborAdvertSize = ICMPv6HeaderSize + NDPNAMinimumSize + NDPLinkLayerAddressSize - // ICMPv6EchoMinimumSize is the minimum size of a valid ICMP echo packet. + // ICMPv6EchoMinimumSize is the minimum size of a valid echo packet. ICMPv6EchoMinimumSize = 8 + // ICMPv6ErrorHeaderSize is the size of an ICMP error packet header, + // as per RFC 4443, Apendix A, item 4 and the errata. + // ... all ICMP error messages shall have exactly + // 32 bits of type-specific data, so that receivers can reliably find + // the embedded invoking packet even when they don't recognize the + // ICMP message Type. + ICMPv6ErrorHeaderSize = 8 + // ICMPv6DstUnreachableMinimumSize is the minimum size of a valid ICMP // destination unreachable packet. ICMPv6DstUnreachableMinimumSize = ICMPv6MinimumSize @@ -69,6 +77,10 @@ const ( // in an ICMPv6 message. icmpv6ChecksumOffset = 2 + // icmpv6PointerOffset is the offset of the pointer + // in an ICMPv6 Parameter problem message. + icmpv6PointerOffset = 4 + // icmpv6MTUOffset is the offset of the MTU field in an ICMPv6 // PacketTooBig message. icmpv6MTUOffset = 4 @@ -89,9 +101,10 @@ const ( NDPHopLimit = 255 ) -// ICMPv6Type is the ICMP type field described in RFC 4443 and friends. +// ICMPv6Type is the ICMP type field described in RFC 4443. type ICMPv6Type byte +// Values for use in the Type field of ICMPv6 packet from RFC 4433. const ( ICMPv6DstUnreachable ICMPv6Type = 1 ICMPv6PacketTooBig ICMPv6Type = 2 @@ -109,7 +122,18 @@ const ( ICMPv6RedirectMsg ICMPv6Type = 137 ) -// ICMPv6Code is the ICMP code field described in RFC 4443. +// IsErrorType returns true if the receiver is an ICMP error type. +func (typ ICMPv6Type) IsErrorType() bool { + // Per RFC 4443 section 2.1: + // ICMPv6 messages are grouped into two classes: error messages and + // informational messages. Error messages are identified as such by a + // zero in the high-order bit of their message Type field values. Thus, + // error messages have message types from 0 to 127; informational + // messages have message types from 128 to 255. + return typ&0x80 == 0 +} + +// ICMPv6Code is the ICMP Code field described in RFC 4443. type ICMPv6Code byte // ICMP codes used with Destination Unreachable (Type 1). As per RFC 4443 @@ -153,6 +177,11 @@ func (b ICMPv6) Code() ICMPv6Code { return ICMPv6Code(b[1]) } // SetCode sets the ICMP code field. func (b ICMPv6) SetCode(c ICMPv6Code) { b[1] = byte(c) } +// SetTypeSpecific sets the full 32 bit type specific data field. +func (b ICMPv6) SetTypeSpecific(val uint32) { + binary.BigEndian.PutUint32(b[icmpv6PointerOffset:], val) +} + // Checksum is the ICMP checksum field. func (b ICMPv6) Checksum() uint16 { return binary.BigEndian.Uint16(b[icmpv6ChecksumOffset:]) |